#include<stdio.h>
#include<conio.h>
main()
{
	float a,b,c,d;
	printf("Program : calculate adding numbers\n");
	printf("input A:");
	scanf("%g",&a);
	printf("input B:");
	scanf("%g",&b);
	printf("input C:");
	scanf("%g",&c);
	d=0.5*a*b*c;
	printf("\nOut put:%g",d);
	printf("\nBy : Kasidis Junkham No.1");
}